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Effect of Transverse Base Width Restraint on the Cracking Behavior of Massive Concrete
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The effect of considering the third dimension in mass concrete members on its cracking behavior is investigated in this study. The investigation includes thermal and structural analyses of mass concrete structures. From thermal analysis, the actual temperature distribution throughout the mass concrete body was obtained due to the generation of heat as a result of cement hydration in
addition to the ambient circumstances. This was performed via solving the differential equations of heat conduction and convection using the finite element method. The finite element method was also implemented in the structural analysis adopting the concept of initial strain problem. Drying shrinkage volume changes were calculated using the procedure suggested by ACI Committee 209 and inverted to equivalent temperature differences to be added algebraically to the temperature differences obtained from thermal analysis. Willam-Warnke model with five strength parameters is used in modeling of concrete material in which cracking and crushing behavior of concrete can be included. The ANSYS program was employed in a modified manner to perform the above analyses.
A thick concrete slab of 1.5m in thickness and 10m in length was analyzed for different widths 2, 4, 8, and 10m to produce different aspect ratios (B/L) of 0.2, 0.4, 0.8, and 1.0 respectively. The results of the analyses show an increase in cracking tendency of mass concrete member as the aspect ratio of the same member is increased due to the effect of transverse base restraint. Accordingly, such effect cannot be ignored in the analysis of base restrained mass concrete structures subjected to temperature and drying shrinkage volume changes.

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Publication Date
Wed Sep 01 2010
Journal Name
Al-khwarizmi Engineering Journal
A Study of the Effect of Kaolin as a Fuel Oil Additive on the Corrosion Inhibition of Fireside Superheater Boiler Tubes
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The objective of the present study is to determine the effect of Kaolin as a fuel oil additive to minimize the fireside corrosion of superheater boiler tubes of ASTM designation (A213-T22) by increasing the melting point of the formed slag on the outside tubes surface, through the formation of new compounds with protective properties to the metal surface. The study included measuring corrosion rates at different temperatures with and without additive use with various periods of time, through crucible test method and weight loss technique.

      A mathematical model represents the relation between corrosion rate and the studied variables, is obtained using statistical regression analysis. Using this model,

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Publication Date
Tue Jan 30 2018
Journal Name
Iraqi Journal Of Science
Study the Effect of a Single Layer of Anti-reflective Coating (Ge) on the Quantitative Efficiency of a Silicon Solar Cell
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The objective of this research is to study the possibility of reducing the reflectivity of the front surface of a silicon cell (Si / Si) by using a theoretical design for a single-layer Antireflection Coatings with a thickness of one quarter of the design wavelength. Then, Mathematical programs in MATLAB (10) were designed to study the quantitative efficiency of the cell as a function of the change in the particle size of the coating within the range (400 - 700 nm) wavelength of the visible state of the vertical and oblique state at the (45°) angle. (Ge) was used as an anti-reflective material. It was found that the highest quantitative efficiency was (96.9004%) at design wavelength (λ0= 550 nm)

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Publication Date
Fri Jan 20 2023
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Effect of the Crude Terpenoids Compounds of Melia Azedrach Leaves and Fruits on Some Biological Aspects of Whitefly Bemisia tabaci
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This study was carried out to determine the effects of crude terpenoid compound extracts of Melia azedarach L. leaves and fruits on some biological aspects of whitefly Bemisia tabaci (Genn.) under laboratory conditions of 25 ± 2°C and relative humidity of 65-70%. The results indicated a significant effect on eggs and immature stages when treated with 0.5, 1, 1.5, and 2 mg/ml of leaves and fruits. The mortality rate increased with concentration. It reached 98.68, 100, 100, 95.70, 86.30, and 42.68% for eggs, 1st, 2nd, and 3rd nymphal instars, pupa, and adults, respectively, at a concentration of 2 mg/ml for leaves extract. At the same time, it reached 94.86, 100,100, 100, 87.89, and 44.90% for eggs, 1st, 2nd, and 3r

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Publication Date
Sun Oct 07 2012
Journal Name
Journal Of Educational And Psychological Researches
The Effect of KWL Strategy on the Achievement of the Students of the fourth class literary in the subject of History and the Development of Cognitive Thinking skills
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Whereas conventional methods of teaching history do not meet the sometimes purpose has suggested some educators strategies modern help to improve the level of students in the education process through activating prior knowledge and employed in positions of current learning, and focus attention on the points and the outstanding elements of the content and practice techniques Calendar criticof ideas and meanings and mental and linguistic activities used to verify the extent of reaching understanding.                                       &n

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Publication Date
Fri Jan 01 2021
Journal Name
Psychology And Education
The effect of Daniel's model on the development of critical thinking in the subject of Arabic language among students of the College of Management and Economics
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This research aims to identify the impact of Daniel's model on the development of critical thinking. In order to achieve this objective, the following hypotheses are formulated: 1. There is no statistically significant difference at the significance level (0.05) between the average differences in the posttest scores of the experimental group taught according to Daniel's model and the control group taught according to the traditional method in the measure of critical thinking. 2. There is no statistically significant difference at the significance level (0.05) between the average differences in the preand post-tests scores of the experimental group taught according to Daniel's model in the measure of critical thinking. The current research i

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Publication Date
Thu Jan 16 2020
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Fulfill the Requirements of Financial Authority For Adoption Of Financial statements in determining The Tax Base: بحث تطبيقي في الهيئة العامة للضرائب لعينة من الشركات المحدودة
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The Financial authority is considered as one of  the most of benefited parts from financial statements  which depends on it in process of accounting  in taxes as basis to determine The Tax Base , but no confidence from financial authority part in objectivity of income financial information in them for many of limited companies led to no dependence on them to specify taxation contain & dependence on yearly regulations that issued them. To enhance the confidence of financial authority to these lists must meet its requirements, because the menus Fulfill the requirements of the financial authority increases the confidence in these statements and therefore reliable in determining the tax base. So this research aims to speci

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Publication Date
Fri Feb 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
Effect of IFRS 16 on the quality of financial reporting For the Iraqi economic units Applied to the General Company of Iraqi Airways
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The rental activity receives "significant" interest from accounting organizations interested in issuing accounting standards worldwide, such as the Financial Accounting Standards Board (FASB), the International Accounting Standards Board (IASB). As leases represents an important source of finance for economic units as an alternative to financing assets through purchase or borrowing. Professional organizations have focused on addressing the situation of extra-budgetary funding through which the lessee hides many leases that are classified as financing without It shows in the budget, which gives an incorrect picture of the reality of the financial situation of economic unity, IASB has issued IFRS 16, which terminates off- Balance s

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Publication Date
Tue Jan 01 2013
Journal Name
العلوم التربوية والنفسية
The effect of a strategy for creative thinking on the achievement of chemistry and the reading comprehension ability of secondary school female students
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Publication Date
Sun Jun 30 2019
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Evaluation the Effect of Velocity and Temperature on the Corrosion Rate of Crude Oil Pipeline in the Presence of CO2/H2S Dissolved Gases
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In this paper investigate the influences of dissolved CO2/H2S gases, crude oil velocity and temperature on the rate of corrosion of crude oil transmission pipelines of Maysan oil fields southern Iraq. The Potentiostatic corrosion test technique was conducted into two types of carbon steel pipeline (materials API 5L X60 and API 5L X80). The computer software ECE electronic corrosion engineer was used to predict the influences of CO2 partial pressure, the composition of crude oil, flow velocity of crude oil and percentage of material elements of carbon steel on the rate of corrosion. As a result, the carbon steel API 5L X80 indicates good and appropriate resistance to corrosion compared to carbon steel API

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Publication Date
Fri Dec 29 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Effect of Using the Computer in Teaching Physics to the Fifth Secondary Grade on the Achievement of Students and Their Retention of Information
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The aims of research is to know the effect of using the computer in

teaching physics to the fifth secondary grade on the achievement of the students and their retention of  information .

The sample consists of ( 50 ) students in the fillh secondary grade (scicnti fie  branch  )   in  Nassiriyah   secondary  school   in  Thi-qar governorate in ( 200 I - 2002 ) that chooses as random Iy and divided

to t>vo equivalent groups:control and experimental .

The researcher built the teaching plans of each group . The five lessons choice from curriculum , and desi b'Tl  five computer teaching programs , and final achievement test from multip

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